解:原式=a-a+2/3b-3/2a+1/3b =b-3/2a ∵ (a-3)+│b+2│=0 ∴(a-3)=0且│b+2│=0 即a-3=0,b+2=0 ∴a=3,b=-2 代入上式得:3-3/2×(-2)=12希望采纳